I get the Warning: comparison between pointer and integer

Question

I am confused as to why I get this warning[Warning] comparison between pointer and integer

while (fread(&searchrecord, sizeof(record), 1, fl) != NULL)

How I fix it?

Answer 1

fread returns a size_t value which is an unsigned integral type. Your platform is defining NULL as (void*)0 which is a pointer type.

Your compiler issues a warning since you're comparing these unrelated types.

The solution is to drop the != NULL in your condition:

while (fread(&searchrecord,sizeof(record),1,fl))

which is clearer anyway.

Answer 2

fread returns the number of items successfully read from the stream. You should compare that to the actual number you passed:

while (fread(&searchrecord, sizeof(record), 1, fl) == 1)

If you try and read more than one item, you should store the return value and compare that to 0 .